1886.] *'"" IWyckoff. 



is high ; the length of the hest preserved one 18 mm , the breadth 3-4 mm . 

 There are no traces of a division into endopodites and exopodites ; but we 

 should regard the parts preserved as the homologues of the exopodites of 

 Nebalia ; there are no traces of seta? on the edges. The general appearance 

 of the appendage is much as in PI. xxxvii, Fig. 6, of our monograph of 

 North American Phyllopod Crustacea. Length of the carapace 46 mm : 

 height at the highest part, 26 ; at the anterior end 12-13 mm . 



From the foregoing description it seems reasonable to suppose that in 

 the fossil forms, Ceratiocaris and allied forms at least, the thoracic feet 

 were, in shape and structure, homologous with those of the modern 

 Nebalia. 



Beyond the feet, at the larger or posterior end of the carapace is the 

 impression of what may have been the basal joint of one of the basal 

 abdominal feet, which joint in Nebalia is as long as the lamellate thoracic 

 appendages ; but this, of course, is quite problematical. 



It is not a little strange that no undoubted traces of the antennae or 

 basal abdominal limbs of any extinct Phyllocaridan have as yet been 

 brought to light ; but the discovery of these large, broad, thin, lobular 

 appendages which most probably belonged to the thorax, makes it all 

 the more likely that the extinct Phyllocarida had antenna?, and basal 

 abdominal limbs similar to those of the existing Nebalia. 



Explanation of the Plate. 



Fig. 1. Cast of carapace of Cryptozoe problematicvs Pack., natural size. 

 Fig. 2. Reverse of the same, showing the impressions of the lamellate 

 feet originally attached to the thorax. 



The Use of Oil in Storms at Sea. By Lieut. A. B. Wyckoff, U. S. N. 



{Read before the American Philosophical Society, April 2, 18S6.) 



My attention was drawn to this subject in 1884, soon after I took charge 

 of the Branch Hydrographic Office in Philadelphia. Several Masters of 

 vessels described their methods of using it, and the striking results of their 

 practical experiments. I became convinced of its great utility ; and in 

 November, 1884, reported the matter in a letter to the Hydrographic 

 Office. Soon afterwards, orders were given the branch offices, to collect 

 all the information they could obtain regarding its use ; and in January, 

 1885, the data, thus collected, was published upon the monthly North 

 Atlantic Pilot Chart. This has been continued ever since, and the Hydro- 

 grapher, Commander J. R. Bartlett, has done everything in his power to 

 interest mariners in the subject. In consequence, where one vessel for- 

 merly used it, there are probably now fifty prepared for such an emergency. 



